#include <iostream>
using namespace std;
const int m = 1000000007;
int main(){
long long n;
cin>>n;
if (n1){
cout << 1 << endl;
return 0;
}if (n2){
cout << 2 << endl;
return 0;
}
long long dp[n + 1];
dp[1] = 1;
dp[2] = 2;
for (int i=3;i<=n;i++){
dp[i]=(dp[i-1]+dp[i-2])%m;
}
cout<<dp[n]<<endl;
return 0;
}
